Renewable energyRenewable energy is a source of energy that can never be exhausted.
We can obtain renewable energy from the sun (solar energy), from the water (hydropower), from the wind (windmills), from hot dry rocks, magma, hot water springs (geothermal) and even from firewood, animal manure, crop residues and waste (Biomass).

According to Nature, a European-funded project has be launched to store gigawatts of electricity created from wind into the refrigerated warehouses normally used to store food. As the production of wind energy is variable every day, it cannot be easily accommodated on the electricity grid. So the "Night Wind" project wants to store wind energy produced at night in refrigerated warehouses and to release this energy during daytime peak hours. The first tests will be done in the Netherlands this year. And as the cold stores exist already, practically no extra cost should be needed to store as much as 50,000 megawatt-hours of energy.

Here is how Nature describes the — simple, but brilliant — idea behind this project.

The idea seems simple. Say you lowered the temperature of all large coldstores in Europe by just 1°C during the night when electricity demand is low, then let it rise 1°C by switching them off during the day when demand is at peak. The net effect would be that the warehouses would act as batteries — potentially storing 50,000 megawatt-hours of energy — and the food wouldn't melt.

Before going further, below is a diagram illustrating the idea: wind energy is optimally stored or released by following the electricity consumption patterns (Credit: Night Wind project)

In European jargon, the official denomination of the Night Wind project is "Grid Architecture for Wind Power Production with Energy Storage through load shifting in Refrigerated Warehouses." And it is led by Sietze van der Sluis, head of refrigeration and heating technology at The Netherlands Organization for Applied Scientific Research (TNO) in Delft.